Description

In 1928, Robert Van de Graaff designed an electrostatic generator that could function as a particle accelerator. When he moved to MIT in 1932, he built it. John Trump, then a doctoral student, worked with Van de Graaff to improve the original design. Over the next 15 years, they worked on vacuum-insulated generators, culminating in the 1947 Rockefeller generator. When it opened as a particle accelerator in 1950, it could operate at 12,000,000 volts—then the most powerful generator in the world.